Ventilation: Approved Document F, Volume 1 — Dwellings

F1(1) O N L I N E V E R S I O N Table 1.5 Performance testing standards Equipment type Test standard Intermittent extract fans BS EN 13141-4 Cooker hoods BS EN 13141-3 Background ventilators without humidity control BS EN 13141-1, clauses 5.1 and 5.2 Background ventilators should meet the performance standards for both of the following: a. air flow from outside to inside the dwelling b. air flow from inside the dwelling to outside Continuous mechanical extract ventilation systems BS EN 13141-6 Mechanical ventilation with heat recovery BS EN 13141-7 BS EN 13141-8 – for internal and external leakage and for mixing, the unit should meet at least Class U4 of the standard Control of ventilation 1.33 Ventilation should be controllable. Controls may be either manual (i.e. operated by the occupant) or automatic. 1.34 Background ventilators should be at least 1700mm above floor level, to reduce cold draughts, but still be easy for the occupant to reach. NOTE: Background ventilators are intended to normally be left open. 1.35 Continuously running fans should be set up to operate without occupant intervention but may have manual or automatic controls for selecting the high rate of operation. Any manual high rate controls should be provided locally to the spaces being served, e.g. bathrooms and kitchens. Automatic controls might include sensors for humidity, occupancy/usage and pollutant release. 1.36 Controls based on humidity sensors may be installed in moisture-generating rooms (e.g. kitchen or bathroom) but should not be used for sanitary accommodation, where odour is the main pollutant. 1.37 Other types of automatic controls might be suitable. Where present, automatic controls should operate according to the need for ventilation in the space. Background ventilators with automatic controls should also have manual override. NOTE: Where a combustion appliance is installed, any automatic controls must also ensure that the ventilation provided meets the requirements of Part J of the Building Regulations. Ventilation systems for dwellings with basements 1.38 In addition to paragraphs 1.12 to 1.37, the performance required for ventilation systems for dwellings with basements would be achieved by following the guidance in paragraphs 1.39 to 1.41. 1.39 A dwelling that includes a basement connected to the above ground parts of the dwelling by a large permanent opening (e.g. an open stairway), may be treated as a multi-storey dwelling when following the guidance in this approved document for dwellings without basements. NOTE: If a basement has only one exposed façade, the guidance for natural ventilation given in this approved document would not be appropriate. In such cases, expert advice should be sought. 12 Approved Document F Volume 1, 2021 edition Building Regulations 2010 O N L I N E V E R S I O N